The modern communications era has brought about a tremendous expansion of wireline and wireless networks. Computer networks, television networks, and telephony networks are experiencing an unprecedented technological expansion, fueled by consumer demand. Wireless and mobile networking technologies have addressed related consumer demands, while providing more flexibility and immediacy of information transfer.
Current and future networking technologies continue to facilitate ease of information transfer and convenience to users. Such increased ease of information transfer and convenience to users has recently been accompanied by an increased ability to provide mobile communications at a relatively low cost. Accordingly, mobile communication devices are becoming ubiquitous in the modern world. With the rapid expansion of mobile communications technology, there has been a related rapid expansion in those services that are demanded and provided via mobile communication devices.
Over the history of mobile communications, there have been many different generations of systems developed to enable the use of such communication devices. The first generations of these systems were sometimes developed independently and, at least initially, were not necessarily usable in cooperation with other systems. However, cooperation between communication system developers began to be employed so that new technologies could be enabled to have the potential for synergistic cooperation with other technologies in order to increase overall capacity. Thus, a mobile terminal operable in second generation (e.g., 2G) systems such as GSM (global system for mobile communications) or IS-95, which replaced the first generation of systems, may in some cases be useable in cooperation with newer generation systems such as third generation systems (e.g., 3G) and others that are currently being developed (e.g., E-UTRAN (Evolved Universal Terrestrial Radio Access Network)).
The ability of a particular mobile terminal to access multiple systems or communicate via multiple radio access technologies (multi-RAT) is sometimes referred to as “multi-radio access” (MRA). An MRA capable terminal may therefore be enabled to transfer between different RATs (e.g., UTRAN, E-UTRAN, GERAN (GSM EDGE radio access network)). During a PS (packet switched) handover of a mobile terminal that is multi-RAT communication capable, the source RAT (e.g., the RAT with which the mobile terminal is in communication prior to handover) and the target RAT (e.g., the RAT with which the mobile terminal is in communication after completion of the handover) may conduct communications regarding the capabilities of the mobile terminal. As an example, in an inter-RAT PS handover between GERAN/UTRAN/E-UTRAN the “source adapts to target” principle is currently typically followed such that the source RAT node may send the mobile terminal capabilities in a format expected by the target RAT node. Thus, for example, a source RAT node in GERAN may be required to initiate a handover to a UTRAN target node by encoding a “Source to Target Transparent Container” as “Source RNC (radio network controller) to Target RNC Transparent Container”, which may be the format expected by the target RNC. As another example applicable to E-UTRAN, a source RAT node in GERAN initiating a handover to E-UTRAN may encode the Source to Target Transparent Container as “Source eNB (evolved node B) to Target eNB Transparent Container”, which may be the format expected by the target eNB. The same “source adapts to target” principle holds true in the other direction as well (e.g., from UTRAN or E-UTRAN to GERAN).
In situations in which a mobile terminal supports more RATs than just the two RATS (e.g., source and target) involved one particular handover, a target RAT receiving mobile terminal capabilities may not receive information for every RAT with which the mobile terminal is capable of communicating. This may impact future handovers since the current target RAT may not be aware of the necessary capabilities for encoding the “Source to Target Transparent” container as expected by the next target RAT. As an example, in the case of a PS handover from E-UTRAN to GERAN, the lack of being able to provide the necessary capabilities to the target RAT may lead to a handover initiation failure towards a target UTRAN. Accordingly, changes to the information exchanged for inter-RAT handovers may be desirable.